Chronic stress increases the stress hormone cortisol and affects many brain functions, putting you at risk for a host of mental conditions.
Stress is an unavoidable part of modern life.
There are two main kinds of stress — acute stress and chronic stress — and not all stress is bad for you.
Acute stress is the reaction to an immediate threat, commonly known as the “fight or flight” response.
Once the threat has passed, your levels of stress hormones return to normal with no long-lasting effects.
Some degree of acute stress is even considered desirable as it primes your brain for peak performance. (1)
But chronic stress — the kind most of us face day in, day out — is a killer.
90% of doctors’ visits are for stress-related health complaints. (2)
Chronic stress makes you more vulnerable to everything from cancer to the common cold. (3)
The non-stop elevation of stress hormones not only makes your body sick, it negatively impacts your brain as well.
Chronic stress changes your brain’s function and even its structure down to the level of your DNA. (4)
The Dangers of Cortisol
Before we look at the many ways chronic stress affects your brain, we need to talk a little bit about stress hormones.
Adrenaline is the stress hormone produced on an “as needed” basis in moments of extreme excitement.
It will help you think and move fast in an emergency.
In the right situation, it can save your life.
It doesn’t linger, dissipating as quickly as it was created.
Cortisol, on the other hand, streams through your system all day long, and that’s what makes it so dangerous.
This stress hormone has been called “public enemy #1.” (5)
Chronic stress takes a toll on adrenal glands.
It can leaving you feeling exhausted, and “wired but tired.” (9)
Weight gain, mood swings, poor sleep, short attention span, and memory issues are common signs of stress due to elevated cortisol. (10)
The Effects of Stress on Your Brain
While stress and cortisol take a toll on your body, they take an equally high toll on your brain.
But most of these effects of stress on your brain are “behind the scenes.”
You don’t notice they’re happening but you will notice the side effects … eventually.
Here are 12 ways chronic stress impacts your brain health and mental well-being along with simple steps you can take to counteract the damage.
1. Stress creates free radicals that kill brain cells.
Cortisol creates a surplus of the neurotransmitter glutamate. (11)
Glutamate creates free radicals — unattached oxygen molecules — that attack brain cells much in the same way that oxygen attacks metal, causing it to rust. (12)
Free radicals actually punch holes in the brain cell walls, leading them to rupture and die.
Stress also indirectly contributes to other lifestyle habits that create more free radicals.
If stress causes you to lose sleep, eat junk food, drink too much alcohol, or smoke cigarettes to relax, these are contributing to your free radical load.
2. Stress makes you forgetful and emotional.
Forgetfulness may be one of the first signs of stress you’ll notice. (13)
Misplaced keys and forgotten appointments have you scrambling, further adding to your stress.
If you find all this stress is making you more emotional too, there’s a physiological reason for this.
Studies show that when you’re stressed, electrical signals in the brain associated with factual memories weaken while areas in the brain associated with emotions strengthen. (14)
3. Stress creates a vicious cycle of fear and anxiety.
Stress builds up an area of your brain called the amygdala.
This is your brain’s “fear center.”
Stress increases the size, activity level and number of neural connections in this part of your brain.
This makes you more fearful, causing a vicious cycle of even more fear and stress. (15)
4. Stress halts the production of new brain cells.
Every day you lose brain cells, but every day you have the opportunity to create new ones.
Brain-derived neurotrophic factor (BDNF) is protein that’s integral in keeping existing brain cells healthy and stimulating new brain cell formation.
BDNF can offset the negative effects of stress on the brain. (16)
It’s been compared to “fertilizer” for the brain.
But cortisol halts the production of BDNF resulting in fewer new brain cells being formed. (17)
Lowered levels of BDNF are associated with brain-related conditions including depression and Alzheimer’s disease. (18)
5. Stress depletes critical brain chemicals causing depression.
Your brain cells communicate via brain chemicals called neurotransmitters.
Low levels of either of these neurotransmitters can leave you depressed and more prone to addictions.
Serotonin is called the “happy molecule.”
It plays a large role in mood, learning, appetite control, and sleep.
Dopamine is the “motivation molecule.”
It’s in charge of your pleasure-reward system.
Too little dopamine can leave you unfocused, unmotivated, lethargic, and depressed.
People low in this brain chemical often use caffeine, sugar, alcohol, and illicit drugs to temporarily boost their dopamine levels.
Serotonin-based depression is accompanied by anxiety and irritability, while dopamine-based depression expresses itself as lethargy and lack of enjoyment of life. (26)
6. Stress puts you at greater risk for mental illnesses of all kinds.
The root cause of most mental illnesses is not yet understood.
Most likely the answers will be a complex variety of factors.
Recent research has discovered physical differences in the brains of people with stress disorders.
Their ratio of the brain’s white matter to gray matter is higher. (27)
Stress predisposes you to developing a variety of mental illnesses including anxiety and panic disorders, depression, PTSD, schizophrenia, bipolar disorder, drug addiction and alcoholism. (28, 29, 30)
7. Stress makes you stupid.
Stress can cause your brain to seize up at the worst possible times — exams, job interviews, and public speaking come to mind. (31)
This is actually a survival mechanism.
If you’re faced with a life and death situation, instinct and training take over from rational thought and reasoning.
This might keep you from being eaten by a tiger, but in modern life this is rarely helpful.
It negatively impacts every cognitive function. (34)
8. Stress shrinks your brain.
Stress can measurably shrink your brain.
Cortisol can kill, shrink, and stop the generation of new neurons in the hippocampus, the part of your brain that stores memories.
Stress also shrinks the prefrontal cortex.
This negatively affects decision making, working memory, and control of impulsive behavior. (37)
9. Stress lets toxins into your brain.
Your brain is highly sensitive to toxins of every kind.
The blood-brain barrier is a group of highly specialized cells that acts as your brain’s gatekeeper.
This semi-permeable filter protects your brain from harmful substances while letting needed nutrients in.
Stress makes the blood-brain barrier more permeable or “leaky.” (38)
This lets things into the brain you don’t want there such as pathogens, heavy metals, chemicals, and other toxins.
Having a leaky blood-brain barrier is associated with brain cancer, brain infections, and multiple sclerosis. (39)
10. Stress increases your risk of dementia and Alzheimer’s.
One of the most worrying effects of stress on the brain is that it increases your risk for dementia and Alzheimer’s.
Being diagnosed with Alzheimer’s disease is the #1 health fear of American adults, even more so than cancer.
Alzheimer’s is now the 6th leading cause of death.
One in three US seniors will die with Alzheimer’s or other forms of dementia. And it’s the most expensive disease in the country. (40)
There is no simple “magic bullet” to prevent Alzheimer’s.
Common sense advice includes eating a healthy diet low in sugar and high in brain-healthy fats, getting physical exercise, not smoking, staying mentally active, avoiding toxic metal exposure, and minimizing stress. (41, 42)
It’s been found that stress, particularly stress that occurs in midlife, increases risk of Alzheimer’s.
Anxiety, jealousy and moodiness in middle age doubles your risk of developing Alzheimer’s. (43)
Chronic stress and elevated cortisol is known to lead to dementia in the elderly. (44)
11. Stress causes brain cells to commit suicide.
Stress leads to premature aging on a cellular level, causing cells in both your body and your brain to commit suicide prematurely.
To understand how this happens, we need to take a look at a part of your chromosomes called telomeres.
You may recall from high school biology that when a cell divides, it passes on the genetic material to the next cell via chromosomes.
Telomeres are protective endcaps on our chromosomes similar to the plastic tips on shoelaces.
(You can see telomeres dyed red in the image to the left.)
Every time a cell divides, the telomeres get a little shorter.
When they reach a critically shortened length, they tell the cell to stop dividing, acting as a built-in suicide switch.
Subsequently the cell dies.
Shortened telomeres lead to atrophy of brain cells and longer telomere length leads to the production of new brain cells. (45)
Telomere length may be the most important indicator of biological age and disease risk.
Some researchers believe it’s a better predictor of your risk for age-related diseases like Alzheimer’s, heart disease, diabetes, and cancer than conventional diagnostic tools. (46)
12. Stress destroys your happiness and peace of mind.
Stress hugely affects the way you think and feel.
It can wear you down mentally and emotionally, and sap the joy from life.
Some signs of stress that impact your mental well-being include:
- excessive worry and fear
- anger and frustration
- impatience with self and others
- mood swings, crying spells or suicidal thoughts
- insomnia, nightmares, disturbing dreams
- trouble concentrating and learning new information
- racing thoughts, nervousness
- forgetfulness, mental confusion
- difficulty in making decisions
- feeling overwhelmed
- irritability and overreaction to petty annoyances
- excessive defensiveness or suspiciousness
- increased smoking, alcohol, drug use, gambling or impulse buying
It’s no fun experiencing these stress symptoms. It’s no picnic for those around you either.
Simple Steps to Help a Stressed Brain
We wouldn’t leave you with all this “bad news” with no solutions.
Minimizing stress and protecting your brain against the effects of stress is easier than you might think.
Here are four simple tips to stop stress in its tracks and overcome its harmful effects on your brain.
- Stop free radical damage by eating a diet high in antioxidant-rich foods like fruit, vegetables, dark chocolate, and green tea.
- Increase levels of brain-boosting BDNF by getting daily physical exercise. It doesn’t have to be strenuous. Walking is excellent. So are exercises with strong mind-body orientations like yoga, tai chi, and qi gong.
- Start a daily meditation practice. Meditation not only reduces stress, it’s a proven way to keep your brain young by keeping telomeres long. (47)
- Monitor your thoughts for automatic negative reactions and cognitive distortions. Stress does not come from events in your life as much as it comes from your thoughts about these events. Meditation is the best tool for learning how to master your thoughts.